Although it is uncertain as to what this Performance tester was used on,
it has a flip up chip insert for what appears to be a high density VLSI
chip which would be a departure from Atari normal chip packaging, so far
noone from Atari's CED or HCD divisions had been able to indentify this
tester and its use until recently when an actual Atari 800XL design with
an entirely new chip onboard was found, called the
Atari
800XLCR, codenamed "KERI" after its new chip by the same name which
is a combine Antic/GTIA chip referred to as the CGIA was found, this new
motherboard explains the term "Keri" and now explains the use of the above
test fixture, yet another piece of the puzzle has been found and more questions
answered.